Track topics on Twitter Track topics that are important to you
During post-occlusive reactive hyperemia (PORH) there is a temporary increase in the total hemoglobin + myoglobin (T[Hb+Mb]) signal as measured by near-infrared spectroscopy (NIRS). This transient increase predicts differences in the kinetic responses of deoxy[Hb+Mb] and oxy[Hb+Mb] during PORH. The purpose of this study was to determine whether sigmoidal (Gompertz or logistic) or exponential functions better describe these response curves during PORH. The fit of the three functions (exponential, Gompertz and logistic) to the NIRS responses, as determined from residual sum of squares, was compared using repeated measures ANOVA on Ranks. The Gompertz function provided a better fit to the oxy[Hb+Mb] response curve than did either the exponential or logistic function (χ (2) = 21.7, df = 2, p < 0.001). The logistic function provided a better fit for the deoxy[Hb+Mb] response (χ (2) = 22.9, df = 2, p < 0.001) than did either the Gompertz or exponential functions. For both NIRS signals, the better fitting sigmoidal functions fit the data well, with an average r value of 0.99 or greater. Adipose tissue thickness was correlated with parameters related to signal strength (amplitude, r = 0.86-0.89; baseline, r = 0.67-0.75; all p < 0.001) but was not related to kinetic parameters (time constant and inflection point; p > 0.05 for all comparisons). These results suggest that during PORH distinct sigmoidal mathematical functions best describe the responses of the oxy[Hb+Mb] (Gompertz) and deoxy[Hb+Mb] (logistic) as measured by NIRS. Further, differences in both the kinetic and amplitude aspects for the responses of oxy[Hb+Mb] and deoxy[Hb+Mb] predict the observed transient change in T[Hb+Mb]. Our methods provide a technique to evaluate and quantify NIRS responses during PORH, which may have clinical utility.
Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA.
This article was published in the following journal.
Name: European journal of applied physiology
To examine the efficacy of selective repetitive transcranial magnetic stimulation (rTMS) therapy guided by functional near-infrared spectroscopy (fNIRS) combined with intensive speech therapy (iST) on...
Functional near-infrared spectroscopy (fNIRS) was used to examine hemodynamic responses in the prefrontal cortex (PFC) during noxious thermal pain, induced by thermal stimulations over three different...
Proteins exhibit structural fluctuations over decades of time scales. From the picosecond side chain motions to aggregates that form over the course of minutes, characterizing protein structure over t...
The therapeutic decision to close patent ductus arteriosus in preterm infants entails great uncertainty. Near-infrared spectroscopy is a noninvasive bedside technique used to monitor mixed regional ox...
We demonstrate operation of the first cryogenic 2D linear ion trap (LIT) with mass-selective capabilities. This trap presents a number of advantages for infrared ion "action" spectroscopy studies, par...
The main objective of this study is to evaluate the ability of infrared spectroscopy to discriminate simple hepatic steatosis from NASH
The purpose of this study is to define the reliability and accuracy of Near Infrared Spectroscopy (NIRS) in the detection of intra-compartmental tissue perfusion in injured and noninjured ...
This study is designed to evaluate the technical performance and clinical handling of a coronary catheter that includes two imaging techniques. The catheter being evaluated performs near ...
The main objective of this study is to assess the ability of Fiber-optic Evanescent Wave Spectroscopy (FEWS) to discriminate synovial fluids samples of septic arthritis patients from other...
The purpose of this study is to examine the efficacy of mid-infrared spectroscopy together with Attenuated Total Reflection (ATR), for the detection of gynecological malignancies in real t...
A noninvasive technique that uses the differential absorption properties of hemoglobin and myoglobin to evaluate tissue oxygenation and indirectly can measure regional hemodynamics and blood flow. Near-infrared light (NIR) can propagate through tissues and at particular wavelengths is differentially absorbed by oxygenated vs. deoxygenated forms of hemoglobin and myoglobin. Illumination of intact tissue with NIR allows qualitative assessment of changes in the tissue concentration of these molecules. The analysis is also used to determine body composition.
A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.
Measurement of the regional temperature of the body or an organ by infrared sensing devices, based on self-emanating infrared radiation.
Spectroscopy technique which measures changes in organic compounds by tracking the spectral energy of absorption of HYDROGEN atoms.
That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.
Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...
Blood is a specialized bodily fluid that delivers necessary substances to the body's cells (in animals) – such as nutrients and oxygen – and transports waste products away from those same cells. In vertebrates, it is composed of blo...